In recent years, there is a demand for an ultra-high-definition video signal (4 k or 8 K video signal) with a definition higher than the current HD (High Definition) video signal (2 k video signal), which is a video signal in which one frame is 1920 samples×1080 lines/23.98P-60P, and an image receiving system and an imaging system have been developed.
In the following description, a video signal with a size of m samples by n lines is abbreviated to “m×n”. For example, [3840×2160/60P] indicates [the number of pixels in the horizontal direction]×[the number of lines in the vertical direction]/[the number of frames per second]. In addition, in a primary color signal transmission system, [4:4:4] indicates the ratio of [a red signal R:a green signal G:a blue signal B]. In a color-difference signal transmission system, [4:4:4] indicates the ratio of [a brightness signal Y:a first color-difference signal Cb:a second color-difference signal Cr]. Furthermore, “23.98P-60P” is an abbreviation of 23.98P, 24P, 25P, 29.97P, 30P, 50P, 59.94P, and 60P indicating the frame rate of a progressive signal.
JP-A-2011-172164 discloses a technique which performs mapping in the active period of HD-SDI in the mode B to transmit and receive an image signal in which the number of pixels in one frame is more than the number of pixels defined by an HD-SDI format.
In the mode B disclosed in JP-A-2011-172164, data is multiplexed into each of a video data area and a horizontal auxiliary data space of a 10.692-Gbps stream. Then, 8B/10B conversion is performed for 4-word video/EAV/SAV data included in 6-channel (CH1 to CH6) HD-SDI and the converted data is encoded into a 5-word (50-bits) data block. Then, the data block is multiplexed into the video data area of the 10.692-Gbps stream from the head of SAV in the order of channels.
On the other hand, 8B/10B conversion is performed for the horizontal auxiliary data space of 4-channel (CH1 to CH4) HD-SDI, the converted horizontal auxiliary data space is encoded into a 50-bit data block, and the data block is multiplexed into the horizontal auxiliary data space of the 10.692-Gbps stream in the order of channels. However, the horizontal auxiliary data spaces of HD-SDIs of CH5 and CH6 are not transmitted.